decode{
  if (!handshaked) {
    int pos=buffer.readerIndex();
    buffer.skipBytes(68);
    return buffer.copy(pos,68);
  if (buffer.readableBytes() < 4)   return null;
  final int len=buffer.readInt();
  if (buffer.readableBytes() >= len) {
    try {
      return buffer.slice(buffer.readerIndex(),len);
  finally {
      buffer.skipBytes(len);
 else {
    buffer.readerIndex(pos);
    return null;
}
setHandshaked{ }
